间伐强度对栎类天然次生林幼苗更新的影响

Effect of thinning intensity on seedling regeneration characteristics in natural secondary oak forests

研究了不同间伐强度对栎类(Quercus)天然次生林幼苗更新特征的影响,对河南省桐柏山区、伏牛山区和太行山区中龄栎类天然次生林实施4种强度(对照:%;弱度:21%;中度:35%;重度:54%)的间伐,2年后调查林下幼苗更新密度、更新频度及更新多样性的变化。结果表明:对照、弱度、中度和重度间伐下幼苗更新密度分别为3 750、6 187、4 612和4 925株·hm^(-2);更新幼苗种类数分别为3、3、8和16种; Shannon-Weinner有效多样性指数分别为1. 95、1. 31、2. 65和5. 64。弱度间伐林下幼苗更新密度最大而重度间伐林下幼苗种类数最多,表明弱度间伐能提高林下幼苗天然更新密度,重度间伐强度会导致幼苗数量减少,却有利于树种多样性的维持。

Four thinning intensities (control,weak:21%,moderate:35%,severe:54%) in natural secondary oak forests in Tongbai Mountain area,Funiu Mountain area and Taihang Mountain area of Henan province were used to study the effect of different thinning intensity on the regeneration characteristics of seedlings.Shifts of regeneration density,regeneration frequency,and regeneration diversity of seedlings were measured after two years of forest thinning.The results showed that the regeneration densities and species numbers of the seedlings of the control,weak,moderate and severe thinning treatments were 3 750,6 187,4 612 and 4 925 ind·hm^-2 respectively,and species numbers of the seedlings of the above treatments were 3,3,8 and 16,respectively.The effective diversity indices of Shannon-Weinner diversity of seedlings of the control,weak,moderate and severe thinning treatments were 1.95,1.31,2.65 and 5.64,respectively.The study showed that the regeneration density under the weak thinning treatment was the highest,while the diversities of seedlings under the severe thinning treatment were the highest in natural secondary oak forests,which indicated that weak thinning could increase the natural regeneration density,while excessive thinning intensity would lead to a decrease in seedling numbers,but it would be beneficial to the maintenance of tree species diversity.